GB2126299A - Push-in connector - Google Patents

Description

GB 2 126 299 A 1

SPECIFICATION

An arrangement for a push-in coupling The present invention relatesto an arrangementfor 70 the rapid and simple push-in connection of one end of an elementthrough which medium or pressure is conducted, such as a hose, pipe, duct orsimilar element, for example, and preferably utilising a 10 retaining function in that at leastthe external surface of the said end is constructed of a soft material into which at least one retaining device appertaining to the arrangementcan be pushed to retain the end. The arrangement comprises an outer part, an insertion 15 part disposed therein which may bearthe said retaining devices, and seals disposed in a cavity and ableto co-actwith the external surface of the said end to seal the interior of the outer part and of the medium or pressure-conducting elementfrom the exteriorof the outer part and of the medium or pressureconducting element.

Coupling arrangementforthe push-in connection of hoses, ducts or pipes of various kinds are already known. One such known arrangement can comprise 25 an inserted sleeve which is slit over part of its length in the longitudinal direction to form spring elements which can be urged in the radial direction by means of a nutfor drawing them together, incorporated in the arrangement. On the inner surface of the spring 30 elements there are barb-shaped grooves or ridges which are designed to co-actwith the material of the outersurface of the hose or pipe afterthe end of the hose or pipe has been inserted in the coupling arrangement. Due to the grooves or corresponding 35 shaping the end can be pushed in while atthe same time separation between the hoselpipe and the coupling arrangement is prevented.

The known arrangement also comprises sealing devices which are designed to provide a seal between the outersurface on the end of the hose or pipe which 105 has been pushed into the coupling arrangement and a sealing wall in the coupling arragement.

With the known coupling arrangements the problem arises of providing a suitable sealing arrangement which can function reliably over along period of time. 110 This involves disadvantages, particularly in certain applications such as in brake systems, optical systems, etc., for example, where an interruption may result in serious consequences. In such applications 50 consideration must be given as to whethersuch so-called -plug-in-type coupling arrangements should be used at all. The alternative is to subject the above-mentioned systemsto frequent and expensive servicing and checking.

It is also importantthatthe sealing arrangement should operate in conjunction with the retaining arrangement and the other parts of the coupling arragement so that rapid, simple and long-lasting reliable pushin connection of the hose, pipe, etc. can 60 be obtained despite an otherwise technically simple construction.

The arrangement according to the present invention obviates in particularthe above-mentioned problem, and the new arrangement can be regarded as being 65 characterised primarily in that the insertion part is designed to occupy a retaining or locking position wherein it is movable relative the outer part. Said part is then positioned inside the outer part in front of the above mentioned seals, viewed in the insertion direction of the said end.

As a development of the concept of the invention said seal arrangement comprises two sealing devices disposed one on either side of a guiding device disposed in the said cavity and effecting the guiding-in 75 of the said end while it is actually being pushed in and also continuing to centre the end in the cavity afterthe push-in connection, and in that the said guiding and sealing devices are designed to provide a vibrationdamping double seal, with the sealing devices located 80 spaced apartfrom each other, viewed in the longitu dinal direction of the end.

As a development of the concept of the invention it is proposed thatthe sealing devices can be formed by two separate sealing rings, which are preferably 85 standard, commercially available O-ring seals. Alternatively, the sealing devices, togetherwith the guiding device, can be incorporated to form a single unit disposed in the said cavity. The spacing between the sealing devices is important, and depends on the 90 dimensions or size of the coupling arrangement. Consequently, it is proposed according to the invention that, with the smallestsize of coupling arrangement, the said spacing is at least 0.3 - 0.5 mm. With larger sizes obviouslythe spacing can be substantially 95 greater and may amouritto 8 mm, for example. With intermediate sizes of coupling arrangement a spacing of 2 - 5 mm is preferably chosen.

According to the said developments the cavityfor the guiding and sealing device can have an extent in 100 the axial direction of the coupling arrangement which exceeds the corresponding combined extent of the guiding and sealing devices. In this way, the said respective guiding and sealing devices, orthe single unit if used, can carry out a longitudinal displacement movement in the axial direction, which provides a large amount of adaptabilityto the different types of couplingswhich occur. Obviously, it is basically possible to chose a cavitywith a volume which substantially corresponds to or onlyslightly exceeds the sectional volume of the said guiding and sealing devices.

In accordance with the concept of the invention, the guiding device should have substantially no sealing function relative to the element conducting medium 115 or pressure and the outer part. The guiding device can thus be made with little or no elasticity. The guide device can consequently be made of polytetrafluoroethene, polVoxymethylene, metal - e.g. steel, or a similar material.

The tolerances forthe guiding device relative to the axial wall of the cavity and the hose, pipe, orthe like are also important, and the said further developments allowfor play between the external and internal surfaces of the guiding device relative to the wall of 125 the cavity and the external surface of the hose, pipe, etc., respectively.

In accordancewith the said further developments the said guiding and sealing devices should be arranged in a first outer part elementwhich has an 130 axial through-bore which is divided in the axial GB 2 126 299 A 2 direction intothree different sections with three different diameters. The first section, which is located atthefirstend of the first outer part element, forms the cavityforthe guiding and sealing devices. Asecond 5 section serves as an intermediate section and con tinues intothethird section via a shoulder. Thefirst section hasthe largest diameter, the second section the next largest diameter and the third section the smallest diameter. Thesaid shoulderformsan abut 10 ment surface forthe free endface of theend of the hose orpipe andthus limitsthe distance for which the hose orthe pipe may be inserted.The diameterof the second section corresponds substantially to the exter nal diameterofthe hose orpipe,whilethe diameterof 15 thethird section corresponds substantially to the internal diameterof the hose or pipe.

Viewed inthe push-in direction,the said guiding and sealing devices are disposed behindthe insertion partwhich, by means of a second outer partelement which can be connected onto the first outer part element,takes up a movable orfixed position relative to the first and second outer part elements. The insertion part bearsthesaid retaining devices on its innersurface and is madewith longitudinally extend ing slits in a mannerwhich is known persejorming a 90 spring elementwhich, depending on force transmit ted from the second outer part element, urgesthe retaining devices towards the outersurface ofthe end of the hose or pipe. The force transmitted inthis case 30 depends on the amount of relative longitudinal displacement between the first and the second outer partelements.

The said further developments also allowforthe said guiding and sealing devices, and also the 35 insertion part, to be doubled up. In this way a guiding 100 and sealing device and an insertion part can be mounted in both ends of the outer part, which enables itto be used as a connecting piece forthe ends of two medium or pressure-conducting elements which can 40 be pushed into the arrangement.

With the arrangement proposed above a double sealing arrangement is obtained which is also vibra tion absorbing, so that vibrations transmitted to the connecting arrangement are largely counteracted, with the resuitthatthere is no tendency forthe coupling arrangement and the hose, pipe, etc. to separate.

The end of the hose or pipe involved is guided longitudinally into the coupling arrangement, which has the advantage that any tendency of the hose orthe 115 like to diverge is prevented from causing separation of the hose or pipe.

The new coupling arrangement also fulfils demands for reliable sealing even with high medium pressures, 55 e.g. with pressure of up to 130 bar. Despite the factthat 120 pressure variations in the medium tend to urge the hose or pipe to move in the sealing devices, such movement is effectively prevented by the said guiding device which holds the end of the hose or pipe 60 involved centred in the sealing cavity.

The sealing arrangement is designed to function also in coupling arrangements which are equipped with devices (nuts) which influence the inner sleeve so asto enablethe innersleeveto be both fixed and 65 movable relative to the rest of the coupling arrange- 130 ment.

The new coupling arrangement is suitable for various types of hose and pipe, and the "TRELLFLEX" Air Brake SAE J 844, type 3b hose which is available on 70 the open market can be named as an example. The coupling arrangement can be used as a coupling device (or nipple) for different systems to or from which medium or pressure isto be supplied. The coupling arrangement can also be used as a connect- 75 ing device. The hose orthe like may have external dimensions of 1/4" - 5/8", for example.

An embodimentof an arrangement which displays the significant characteristics of the inventionswill be described in thefollowing byway of example,with 80 reference to the accompanying drawing, onwhich Figure 1 showsa coupling arrangement, partially sectioned, in which the end of a hose is inserted and anchored, Figure 2 is a horizontal view, showing the coupling 85 arrangement in Figure 1 from one end, Figure 3 is a section showing the sealing devices comprised in the coupling arrangement, Figure 4 shows a modified embodiment of the sealing device shown in Figure 3, while Figure 5 shows schematically a coupling arrangement which has been modified compared with the embodiment shown in Figure 1.

Figure 6 shows half the length section of a second embodimentof a coupling arrangement.

In Figure 1 a firstouter partelement is designated 1 and a second outer part element is designated 2. The first outer part element is equipped with a sleeveshaped part 1 a at its first end. On the outer surface of the central part of the outer part element 1 a hexagonal nut 1 b is mounted. At its other end the first outer part element is made with a connecting section 1 cwhich has an outwardlyfacing thread 1 c'. Via this thread the coupling arrangement as a whole can be securely screwed into an element3, to which the coupling 105 arragement isto be attached and which is equipped with a tapped aperture 3a, the thread of which corresponds to the thread 1 c'.

The element 3 represents all the types of element which can be provided with the coupling arrangement 110 in question.

The said sleeve-shaped part la is equippedwith an external thread la'onto which the second outer part element2 can be securelyscrewed via a corresponding internal thread 2a. Thefirstand second outer part elements can be joined together in some otherway than by means of the said threads 1 a'and 2a, such as by means of a bayonetfixing or some othertype of connecting arrangement.

The coupling arrangement is also equipped with an insertion part4with is providedwith a relatively large numberof longitudinally extending slits4a which extend from the innerend of the insertion part towardsthe outerend thereof, where they terminate at a distancefrom the outerend which is approximate- 125 ly 1/5 of thetotal length of the insertion part. The numberof slits may be 6 -8, for example. By means of the slits a spring element4b is formed which can be acted upon in the radial direction by means of the second outer part element 2. The said spring element 4b bears on its innersurface barb-shaped retaining T GB 2 126 299 A 3 devices 4c and 4d which are located at a distance from each other, viewed in the axial direction of the insertion part. The barb-shaped retaining devices are made with radially short lower surfaces and obliquely 5 set and elongated upper surfaces.

The second outer part element has an inwardly facing tapered surface 2b which can co-act with an outwardly facing flange 4e on the insertion part. The tapered surface 2b and the flange 4e are shaped in 10 such away that the position of the spring elements in the radial direction depends on the amount of relative longitudinal displacement between the first and the second outer part elements. The furtherthe second outer part element is drawn onto the first outer part 15 element, the further the spring elements are forced radially inwards, and vice versa.

The first outer part element is also equipped with a so-called snap-off rim 1 d. The said snap-off rim forms a distinctfirst stopping postion forthe second outer 20 part element 2 which rests in the said first distinct stopping postition againstthe upper surface of the snap-off rim via a corresponding abutment surface 2d on its inner end. In the first stopping position accomplished via the snap-off rim the second outer 25 part element 2 holds the spring elements 4b pressed radially inwards by a predetermined amount. The elasticity of the snap-off rim 1 d can also be used so that in this stopping position the snap-off rim func tions as a sprung stop forthe second outer part 30 element.

If it is desired to spring the spring elements in further, the second outer part element can be influ enced, by screwing itfurther on, so thatthe snap-off rim snaps off, after which the second outer part 35 element can be screwed further onto thefirst outer part element so thatfurther longitudinal displacement is achieved between the first and the second outer part elements.

The end of a hose is shown in Figure 1 pushed into the coupling arragement and is designated by the 105 reference numeral 5. The end of the hose appertainsto a device which is designed to conduct medium (hydraulic oil, optical beam conductors, air, etc) and/or pressure in one or both directions. The end of the hose is retained in the coupling arrangement by means of the spring elements 4b and the retaining force can be varied as described above, according to the extentto which the second outer part element is screwed onto the first outer part element 1. With 50 extreme medium pressures the second outer part element can be made to snap off the snap-off rim and further screwing on can take place, resulting in further pressing in of the spring elements towards the end of the hose. The barb-shaped devices 4c and 4d pene trate therelayfurther into the material of the outer surface of the end of the hose, so thatthe radially lower surfaces on the barb-shaped devices couteract any tendency of the end of the hose to be pulled out, while atthe same time allowing the end of the hose to 60 be inserted easily. The inner part 4 may be equipped with a different number of retaining devices 4c, 4d, e.g. one, three, four or more.

The first outer part element is equipped with a longitudinal through-boreforthe medium involved 65 and the said end of the hose. The through-bore has 130 three sections 6,7 and 8. The first section which is located atthe sleeve- shaped part 1 a has the greatest diameter D1. The said first section forms a cavity for the sealing device which is described in more detail in 70 the following. The second section 7 forms an intermediate section and has a diameter D2 which is less than the diameter D1. The third section 8 is located at the rear part of the second outer part element and has the smallest diameter D3. An abutment surface 9 is 75 formed between the second and third sections 7 and 8 The diameter D2 corresponds substantially with the external diameter c11 of the end of the hose and the diameter D3 corresponds substantially with the internal diameter c12 of the end of the hose. The abutment 80 surface 9 forms a stop forthe end face 5a on the end of the hose. The sleeve-shaped part 1 a is equipped atthe frontwith an inwardly-bent flange 1 e to form a cavity 6 forthe said guiding and sealing devices. The said inwardly-bentflange isfixed in the embodiment 85 shown, but it can also be made as a partwhich can be screwed onto the sleeve-shaped part 1 a. Alternatively, the flange may be omitted altogether.

The insertion part4 extends via its inner end 4f to a point level with the said flange 1 e. In the position 90 shown in Figure 1, with the second outer part element 2 screwed tight, the insertion part4 lies loosely inside the second outer part element so that it is able to rotate and move slightly in the axial direction. This means thatthe fixing of the end 5 of the hose or pipe in 95 question is movable to a corresponding extent.

However, when the second outer part element is inf luenced so thatthe snap-off rim 1 cl snaps off, the inner pa rt 4 presses againstthe f lange 1 e so that a rigid connection is achieved between the outer part and the 100 inner part4. If the flange 1 e is omitted, the insertion part is designed so that it is pressed instead against the free end of the sleeveshaped part 1 a thusformed.

In the embodiment example shown in Figure 1, the sealing device comprises preferably two separate sealing devices which in the present case preferably takethe form of two 0-ring seals 10 and 11. The said seals can display a Shore hardness of preferably 70 90. The cavity 6 is made with a gap orwidth which is lessthan the section of the 0-ring seals, so that 110 deformation of the said section occurs when the end involved is pushed into the coupling arrangement. In a non-compressed state the section of the respective 0-ring seals exceeds the cavity gap 6 by approximately 20% of its total diameter. The relative dimensioning 115 of the width of the cavity gap and the section diameter of the seals 10 and 11 is naturally dependent primarily on the Shore hardness selected forthe seals, and can therefore vary between 10 and 40%.

Between the said seal 10 and 11 a guiding device 12 120 is inserted which is not itself designed to have any significant sealing effect againstthe outer surface of the end of the hose and the axial surface 6a of the cavity 6. The guiding device has as its main function the guiding of the end of the hose when it is being 125 pushed into the coupling arrangement, and the holding of the actual part of the end of the hose centred in the cavity 6 afterthe push-in connection has been made. Any movement which the end of the hose might carry out is effectively counter-acted bythe said guiding device. The amount of play, calculated on the diameter, between the guiding device and the wall 6a of the cavity lies within the range of 0.05 - 0.5 mm, a value preferably being chosen within the range 0.1 - 0.3 mm. Relativeto the outersurface of the end of the hose,the innersurface of the guiding device has an 70 amountof play, calculated on the diameter, which is selected within the range 0.02 - 0.5 mm, and preferably within the range 0.05 - 0.2 mm. The length of the guiding device in the axial direction of the coupling 10 arrangement is at least 0.3 - 0.5 mm in the smallest size 75 of the coupling arrangement as such.

With the largest sizes it is conceivable that the said length would be approximately 8 mm orthereabouts.

With normal sizes of the said coupling arrangement a 15 length of appproximately2-3 mm is preferably chosen. In the present case the cavity 6 is made with a longitudinal extent which exceeds the total longitu dinal extent of the guiding and sealing devices 12 and 10,11 respectively. In the Figure the narrowest gap 20 between the boundary surfaces of the sealing devices and 11 has been indicated by A, while the distance between their centres is indicated by X. Due to the guiding device which lies between them the sealing devices 10 and 11 are lodged at a distance from each 25 otherso that an effective double sealing effect is obtained relative to the actual part on the end 5 of the hose. The distances A and A'shown in Figure 1 can varyf rom one coupling to another. It is important that the distance Ashould not be lessthan a predeter 30 mined value, which is determined by the extent of the guiding device in the axial longitudinal direction of the coupling arrangement. In Figure 1 the play between the outersurface of the guiding device and the cavity wall 6a has been designated 13, whilethe play 35 between the innersurface of the guiding device and the outersurface of the end of the hose is designated 14.

The second section 7 has a longitudinal extent in the axial direction of the coupling arrangement which is 40 designated B. This longitudinal extent B is substantial lythe same as or exceeds the length of the guiding device 12 in the same direction. The insertion sleeve has a longitudinal extent which corresponds substan tiallyto the total longitudinal extent of the first and 45 second sections. In this way extremely extensive guiding of the end of the hose is obtained, with the retaining arrangement positioned furthest out and followed by the sealing arrangement. Guiding is terminated bythe third section which also provides a 50 distinct stop via the abutment surface 9. The total length of the guiding effect exceeds or is substantially equal to half the length of the coupling arrangement.

Furthermore, on its innerfree end the insertion part has a guide edge 4f which is guided againstthe inner 55 surface of the inwardly projecting flange 1 e. The parts 1, 2 and 4 are expediently made of metal, e.g. steel, brass, a suitable brass alloy, etc. The material of the hose or pipe 5 may be plastic, rubber or other similar material. The hoses which can be used in this 60 connection are available on the open market, as 125 mentioned above.

Thetop of the second outer part element is provided with a spannergrip 15which is machined out of the material of the said part. The machining has been 65 carried out at a point where the thickness of the 130 GB 2 126 299 A 4 material isgreatest.The nut 1 b is equippedwith a lowergroove in which a seal 16 is inserted. The said seal is provided to seal the lower surface on the element 3 which is not shown, however, in Figure 1.

Figure 3 shows that the narrowest boundary spacing A between the sealing devices 10 and 11 is the same as the length of the guiding device 12. The volume of the cavity 6 exceeds thetotal volume of the guiding and sealing devices. The length of the cavity has been designated C.

As shown in Figure 4,the sealing devices 1 O'and 11' can be integrated with the guiding device 12'to form a single unit. The distances A and Kare fixed in this instance.

The construction shown in Figure 1 provides an embodiment of the coupling arrangement which is intended to be screwed securely on a part, and object, an instrument, etc., via a thread 1 c'. The outer part element 1 can be dispensed with altogether or may be 85 equipped with a valve unit (not shown in Figure 1). With the coupling arrangement a connection is obtained between the inside of the element 3 in question and an element connected to the other end of the hose 5. The principle of the new coupling 90 arrangement can also be applied in the case where the coupling arrangement is serving as a connecting unit between the ends of two hoses. Figure 5 shows this case chematically. In this instance,the coupling unit has been designated 17 and hastwo cavities 6'and 6---.

95 The coupling unit is provided at its respective ends with insertion sleeves 4'and 4-, corresponding to that shown in Figure 4. In the respective cavities sealing devices 10-, 11---and 10-, 11... respectively, and guiding devices 12---and 12-, respectively, are in- 100 serted. In detail, the various parts look and function as described above.

Asthe material forthe sealing devices orthesealing sections in the combination shown in Figure 4, standard sealing rings can be used. The material may 105 be a plastic, such as polytetraflouroethene, polyox ymethylene.

The invention is not restricted to the embodiment illustrated above, but may be subjected to modifications within theframework of the following Patent

Claims (12)

110 Claims and the concept of the invention. Thus, for example, the

section 7 may be tapered somewhat at the end nearestthe abutment surface 9. The tapered wall part may then preferably be approximately 1/2 B or 1/2 -1/4 B and the half cone angel forthe sectjion 7 will

115 be chosen within the range 1 - 5'. The tapered section eliminates the effect of any possible tolerances atthe end of the hose or the like. The tapered part provides definitive centring of the outermost part of the said end.

Figure 6 shows a modified embodimentwhich correspondsto some exteritto the coupling shown in Figure 1. However, there is a tube-shaped counterholding device 18which isfixed (as shown in Figure 6) or loose relativeto the casing 19.The element 18 is used when the hose 20 is made of softer material, and thus endows the coupling with a slit-shaped cavity 21. The cavity 21 extends partthe sealing and centring devices 22, 23 and 24 respectively. The device 18 extends pastthe retaining device 25a on the insertion part 25. The element 26 is sealed againstthe outer 1 GB 2 126 299 A 5 surface 20a of the hose 20 by means of afurther sealing device 27. The part25 inthis embodiment example assumes only a movable retaining or locking position relativetothe parts 19,26 and thus forms an 5 expansible element which allows the insertion of the end 20 of the hose and retention of the end after insertion. The expansible effect is achieved, as in Figure 1, by means of longitudinally extending slits or cut-outs (notshown),the length and numberof which 10 may bevaried according to the degree of retention effectwith whichthe insertion partisto be endowed.

The part25 is guided in a corresponding cut-out26a by a part, preferabiya hollow cylindrical part25b. In this casethecasing part 19a does not havethe abutment flange forthe sealing and centring devices 22,23 and 24 respectively. The end face 25c of the insertion part forms the abutment surface instead. The part 25 is able to carry out a certain amount of axial longitudinal displacement movement in the cut-out 28 so thatthere 20 is a certain amount of movement available for fixing in the hose. The sealing and centring arrangements are as above. The part 24 also functions as a so-called "back-up".

With the construction shown the coupling 19,26 can 25 be prepared for simple automatic assembly, the part 90 26 being endowed with its terminal position before the end of the hose is inserted in the cavity 21. The end of the hose can thereafter be inserted into the position shown in Figure 6 and is directly retained in the 30 coupling duetothe inherent retaining effect of the part 95 25. After assemblythe part26 does not require rotation to lock it in, which simplifies assembly, e.g.

with a robot. The coupling isfastened, preferably before application of the hose, in a partwhich is not 35 shown and in which itshould be possibleto fixthe coupling securely.

CLAIMS 1. An arrangement forthe rapid and simple push-in connection of one end of an elementth rough 40 which medium andfor pressure is conducted, such as a hose, pipe or similar element, for example, and preferably utilising a retaining arrangement where at least the external surface of the said end is made of a soft material into which at least one retaining device 45 appertaining to the arrangement can be forced to retain the end, the arrangement comprising an outer part an insertion part disposed therein which may bearthe said retaining devices, and seals disposed in a cavity and able to co-act with the external surface to the said end to seal the inside of the outer part and of the medium andlor pressure-conducting element from the exterior of the outer part and of the medium andlor pressure-conducting element, and wherein the insertion part is designed to have an inherent retain 55 ing effect of said end and to occupy a retaining position wherein it is movable relative to the outer part, inside the outer part and in front of the said seals, viewed in the insertion direction of the said end.

2. An arrangement according to Patent Claim 1 60 and wherein the said seal arrangement comprises two 125 sealing devices disposed one on either side of a guiding device disposed in the said cavity and effecting the guiding of the said end while it is actually being pushed in and also continuing to centre the end 65 and in the cavity after the push-in connection, and wherein the said guiding and sealing devices are designed to provide a vibration-damping double seal with the sealing devices located spaced apart from each other by a distance viewed in the longitudinal 70 direction of the end.

3. An arrangement according to Patent Claim 2 and wherein the sealing devices consist of two separate sealing rings, preferably O-ring seals which are available as standard parts, orwherein the sealing 75 devices, togetherwith the guiding device, are incor portated in a single unit arranged in the said cavity.

4. An arrangement according to Patent Claim 3 and wherein the narrowest surface-surface gap (A) between the sealing devices is at least 0.3 mm, and is 80 preferably2-5mm.

5. An arrangement according to Patent Claim 2 and wherein the cavity has an extent in the axial direction of the outer partwhich is greaterthan the corresponding combined extent of the guiding and 85 sealing devices, so thatthe respective elements of the guiding and sealing devices, orthe single unit, can carry out a longitudinal displacement movement in the axial direction.

6. An arrangement according to Patent Claim 2, and wherein the guiding device has substantially no sealing function relative to its medium and/or pressure-conducting element and the outer part, and is made with little or no elasicity, and wherein the guiding device is made of polytetrafluoroethene, polyoxymethylene, metal, e.g. steel, or a similar material.

7. An arrangement according to Patent Claim 2 and wherein calculated on the diameter, the guiding device has a first amount of play relative to the axial 100 wall of the cavity which is chosen within the range 0.05 0.5 mm, and preferably withing the range 0. 1 - 0.3 mm, and has a second amount of play relative to the outer surface of the medium and/or pressure- conducting element which is selected within the range 0.02 0.5 mm, and preferably within the range 0.05 - 0.2 mm.

8. An arrangement according to Patent Claim 2 and wherein the said guiding and sealing devices are arranged in a first outer part element which has an axial throughbore which is divided in the axial 110 direction into three different sections with different diameters, the first section, which has the largest diameter and is located at the first end of the outer part element, forming the said cavityforthe said guiding and sealing devices, the second section, which has the 115 next largest diameter and forms a middle section, being designed to accommodate the free part of said end, and the third section, which hasthe smallest diameter, extending outto the other end of the first outer part element, and wherein a shoulder which 120 marks the transition between the second and third sections forms an abutment surface which can co-act with the end edges of the said free part, the said next largest diameter corresponding substantially to the external diameter of the said end, and said smallest diameter corresponding substantiallyto the internal diameter of the said end.

9. An arrangement according to Patent Claim 8, characterised inthatthe said guiding and sealing devices are arranged after the insertion part and, by 130 means of the second outer part element (2) which can 6 GB 2 126 299 A 6 bejoined into the first outer part element (1), this insertion partassumes a movable orfixed position relative to the first and second outer part elements, andthatthe insertion part bears on its innersurface the said retention devices and is also constructed with longitudinally extending slits (4a) to form a spring element (4b) which, depending on force transmitted from the second outer part element, urges the retention devices in the direction of the outer surface 10 ofthesaidend.

10. An arrangement according to Patent Claim 9, characterised in thatthe said guiding and sealing devices are arranged afterthe insertion part(4)which in one and the same arrangement is designed to 15 assume the said second outer part element (2) anda snap-offrim (1d) located on the first outer part elementandwhich in a not snapped off state holds the second outer part element in a first position wherein theinsertion partismovable relative to the first and 20 second outer part elements, and which in a snapped off state allows the second outer part element to take up a second position wherein the insertion part is fixed relative to the first and second outer part elements.

11. An arrangement according to Patents Claim 2, 25 characterised in thatthe said guiding and sealing devices, as well as the insertion part (4), are doubled up, sothatthe outer part (1, 2) bears buiding and sealing devices and an insertion part in both its ends so that it can serve as a connecting units forthe ends of two medium andlor pressure-conducting elements which can be pushed intothe arrangement.

12. An arrangement forthe rapid and simple push-in connection of one end of an element through which medium andlor pressure is conducted, such as 35 a hose, pipe or similar element, for example, constructed, arranged, and adapted for use substantially as hereinbefore described with reference to Figures 1 to 3, or Figure 6, or modified as hereinbefore describedwith referenceto Figure4or5.

P: inted for Her Majesty's Stationery Office by TheTweeddale Press Ltd., Berwick-upon-Tweed, 1984. Published atthe Patent Office,25 Southampton Buildings, London WC2A 1 AYfrom which copies maybe obtained.